/*
* Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
+ * Copyright (C) 2013 - Raphaël Beamonte <raphael.beamonte@gmail.com>
+ * Copyright (C) 2013 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License, version 2 only, as
#include <limits.h>
#include <stdlib.h>
#include <string.h>
-#include <sys/types.h>
#include <sys/stat.h>
+#include <sys/types.h>
#include <unistd.h>
#include <inttypes.h>
#include <regex.h>
+#include <grp.h>
#include <common/common.h>
#include <common/runas.h>
#include "utils.h"
+#include "defaults.h"
/*
- * Return the realpath(3) of the path even if the last directory token does not
- * exist. For example, with /tmp/test1/test2, if test2/ does not exist but the
- * /tmp/test1 does, the real path is returned. In normal time, realpath(3)
- * fails if the end point directory does not exist.
+ * Return a partial realpath(3) of the path even if the full path does not
+ * exist. For instance, with /tmp/test1/test2/test3, if test2/ does not exist
+ * but the /tmp/test1 does, the real path for /tmp/test1 is concatened with
+ * /test2/test3 then returned. In normal time, realpath(3) fails if the end
+ * point directory does not exist.
+ * In case resolved_path is NULL, the string returned was allocated in the
+ * function and thus need to be freed by the caller. The size argument allows
+ * to specify the size of the resolved_path argument if given, or the size to
+ * allocate.
*/
LTTNG_HIDDEN
-char *utils_expand_path(const char *path)
+char *utils_partial_realpath(const char *path, char *resolved_path, size_t size)
{
- const char *end_path = path;
- char *next, *cut_path = NULL, *expanded_path = NULL;
+ char *cut_path, *try_path = NULL, *try_path_prev = NULL;
+ const char *next, *prev, *end;
/* Safety net */
if (path == NULL) {
goto error;
}
- /* Find last token delimited by '/' */
- while ((next = strpbrk(end_path + 1, "/"))) {
- end_path = next;
+ /*
+ * Identify the end of the path, we don't want to treat the
+ * last char if it is a '/', we will just keep it on the side
+ * to be added at the end, and return a value coherent with
+ * the path given as argument
+ */
+ end = path + strlen(path);
+ if (*(end-1) == '/') {
+ end--;
+ }
+
+ /* Initiate the values of the pointers before looping */
+ next = path;
+ prev = next;
+ /* Only to ensure try_path is not NULL to enter the while */
+ try_path = (char *)next;
+
+ /* Resolve the canonical path of the first part of the path */
+ while (try_path != NULL && next != end) {
+ /*
+ * If there is not any '/' left, we want to try with
+ * the full path
+ */
+ next = strpbrk(next + 1, "/");
+ if (next == NULL) {
+ next = end;
+ }
+
+ /* Cut the part we will be trying to resolve */
+ cut_path = strndup(path, next - path);
+
+ /* Try to resolve this part */
+ try_path = realpath((char *)cut_path, NULL);
+ if (try_path == NULL) {
+ /*
+ * There was an error, we just want to be assured it
+ * is linked to an unexistent directory, if it's another
+ * reason, we spawn an error
+ */
+ switch (errno) {
+ case ENOENT:
+ /* Ignore the error */
+ break;
+ default:
+ PERROR("realpath (partial_realpath)");
+ goto error;
+ break;
+ }
+ } else {
+ /* Save the place we are before trying the next step */
+ free(try_path_prev);
+ try_path_prev = try_path;
+ prev = next;
+ }
+
+ /* Free the allocated memory */
+ free(cut_path);
+ };
+
+ /* Allocate memory for the resolved path if necessary */
+ if (resolved_path == NULL) {
+ resolved_path = zmalloc(size);
+ if (resolved_path == NULL) {
+ PERROR("zmalloc resolved path");
+ goto error;
+ }
+ }
+
+ /*
+ * If we were able to solve at least partially the path, we can concatenate
+ * what worked and what didn't work
+ */
+ if (try_path_prev != NULL) {
+ /* If we risk to concatenate two '/', we remove one of them */
+ if (try_path_prev[strlen(try_path_prev) - 1] == '/' && prev[0] == '/') {
+ try_path_prev[strlen(try_path_prev) - 1] = '\0';
+ }
+
+ /*
+ * Duplicate the memory used by prev in case resolved_path and
+ * path are pointers for the same memory space
+ */
+ cut_path = strdup(prev);
+
+ /* Concatenate the strings */
+ snprintf(resolved_path, size, "%s%s", try_path_prev, cut_path);
+
+ /* Free the allocated memory */
+ free(cut_path);
+ free(try_path_prev);
+ /*
+ * Else, we just copy the path in our resolved_path to
+ * return it as is
+ */
+ } else {
+ strncpy(resolved_path, path, size);
}
- /* Cut last token from original path */
- cut_path = strndup(path, end_path - path);
+ /* Then we return the 'partially' resolved path */
+ return resolved_path;
+
+error:
+ free(resolved_path);
+ return NULL;
+}
+
+/*
+ * Make a full resolution of the given path even if it doesn't exist.
+ * This function uses the utils_partial_realpath function to resolve
+ * symlinks and relatives paths at the start of the string, and
+ * implements functionnalities to resolve the './' and '../' strings
+ * in the middle of a path. This function is only necessary because
+ * realpath(3) does not accept to resolve unexistent paths.
+ * The returned string was allocated in the function, it is thus of
+ * the responsibility of the caller to free this memory.
+ */
+LTTNG_HIDDEN
+char *utils_expand_path(const char *path)
+{
+ char *next, *previous, *slash, *start_path, *absolute_path = NULL;
+ char *last_token;
+ int is_dot, is_dotdot;
+
+ /* Safety net */
+ if (path == NULL) {
+ goto error;
+ }
- expanded_path = zmalloc(PATH_MAX);
- if (expanded_path == NULL) {
+ /* Allocate memory for the absolute_path */
+ absolute_path = zmalloc(PATH_MAX);
+ if (absolute_path == NULL) {
PERROR("zmalloc expand path");
goto error;
}
- expanded_path = realpath((char *)cut_path, expanded_path);
- if (expanded_path == NULL) {
- switch (errno) {
- case ENOENT:
- ERR("%s: No such file or directory", cut_path);
- break;
- default:
- PERROR("realpath utils expand path");
- break;
+ /*
+ * If the path is not already absolute nor explicitly relative,
+ * consider we're in the current directory
+ */
+ if (*path != '/' && strncmp(path, "./", 2) != 0 &&
+ strncmp(path, "../", 3) != 0) {
+ snprintf(absolute_path, PATH_MAX, "./%s", path);
+ /* Else, we just copy the path */
+ } else {
+ strncpy(absolute_path, path, PATH_MAX);
+ }
+
+ /* Resolve partially our path */
+ absolute_path = utils_partial_realpath(absolute_path,
+ absolute_path, PATH_MAX);
+
+ /* As long as we find '/./' in the working_path string */
+ while ((next = strstr(absolute_path, "/./"))) {
+
+ /* We prepare the start_path not containing it */
+ start_path = strndup(absolute_path, next - absolute_path);
+
+ /* And we concatenate it with the part after this string */
+ snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 2);
+
+ free(start_path);
+ }
+
+ /* As long as we find '/../' in the working_path string */
+ while ((next = strstr(absolute_path, "/../"))) {
+ /* We find the last level of directory */
+ previous = absolute_path;
+ while ((slash = strpbrk(previous, "/")) && slash != next) {
+ previous = slash + 1;
}
- goto error;
+
+ /* Then we prepare the start_path not containing it */
+ start_path = strndup(absolute_path, previous - absolute_path);
+
+ /* And we concatenate it with the part after the '/../' */
+ snprintf(absolute_path, PATH_MAX, "%s%s", start_path, next + 4);
+
+ /* We can free the memory used for the start path*/
+ free(start_path);
+
+ /* Then we verify for symlinks using partial_realpath */
+ absolute_path = utils_partial_realpath(absolute_path,
+ absolute_path, PATH_MAX);
}
- /* Add end part to expanded path */
- strncat(expanded_path, end_path, PATH_MAX - strlen(expanded_path) - 1);
+ /* Identify the last token */
+ last_token = strrchr(absolute_path, '/');
- free(cut_path);
- return expanded_path;
+ /* Verify that this token is not a relative path */
+ is_dotdot = (strcmp(last_token, "/..") == 0);
+ is_dot = (strcmp(last_token, "/.") == 0);
+
+ /* If it is, take action */
+ if (is_dot || is_dotdot) {
+ /* For both, remove this token */
+ *last_token = '\0';
+
+ /* If it was a reference to parent directory, go back one more time */
+ if (is_dotdot) {
+ last_token = strrchr(absolute_path, '/');
+
+ /* If there was only one level left, we keep the first '/' */
+ if (last_token == absolute_path) {
+ last_token++;
+ }
+
+ *last_token = '\0';
+ }
+ }
+
+ return absolute_path;
error:
- free(expanded_path);
- free(cut_path);
+ free(absolute_path);
return NULL;
}
return ret;
}
+/*
+ * Create pipe and set fd flags to FD_CLOEXEC and O_NONBLOCK.
+ *
+ * Make sure the pipe opened by this function are closed at some point. Use
+ * utils_close_pipe(). Using pipe() and fcntl rather than pipe2() to
+ * support OSes other than Linux 2.6.23+.
+ */
+LTTNG_HIDDEN
+int utils_create_pipe_cloexec_nonblock(int *dst)
+{
+ int ret, i;
+
+ if (dst == NULL) {
+ return -1;
+ }
+
+ ret = utils_create_pipe(dst);
+ if (ret < 0) {
+ goto error;
+ }
+
+ for (i = 0; i < 2; i++) {
+ ret = fcntl(dst[i], F_SETFD, FD_CLOEXEC);
+ if (ret < 0) {
+ PERROR("fcntl pipe cloexec");
+ goto error;
+ }
+ /*
+ * Note: we override any flag that could have been
+ * previously set on the fd.
+ */
+ ret = fcntl(dst[i], F_SETFL, O_NONBLOCK);
+ if (ret < 0) {
+ PERROR("fcntl pipe nonblock");
+ goto error;
+ }
+ }
+
+error:
+ return ret;
+}
+
/*
* Close both read and write side of the pipe.
*/
int utils_mkdir_recursive(const char *path, mode_t mode)
{
char *p, tmp[PATH_MAX];
- struct stat statbuf;
size_t len;
int ret;
ret = -1;
goto error;
}
- ret = stat(tmp, &statbuf);
+ ret = mkdir(tmp, mode);
if (ret < 0) {
- ret = mkdir(tmp, mode);
- if (ret < 0) {
- if (errno != EEXIST) {
- PERROR("mkdir recursive");
- ret = -errno;
- goto error;
- }
+ if (errno != EEXIST) {
+ PERROR("mkdir recursive");
+ ret = -errno;
+ goto error;
}
}
*p = '/';
* Return 0 on success or else a negative value.
*/
LTTNG_HIDDEN
-int utils_create_stream_file(char *path_name, char *file_name, uint64_t size,
- uint64_t count, int uid, int gid)
+int utils_create_stream_file(const char *path_name, char *file_name, uint64_t size,
+ uint64_t count, int uid, int gid, char *suffix)
{
int ret, out_fd, flags, mode;
- char full_path[PATH_MAX], *path_name_id = NULL, *path;
+ char full_path[PATH_MAX], *path_name_suffix = NULL, *path;
+ char *extra = NULL;
assert(path_name);
assert(file_name);
goto error;
}
+ /* Setup extra string if suffix or/and a count is needed. */
+ if (size > 0 && suffix) {
+ ret = asprintf(&extra, "_%" PRIu64 "%s", count, suffix);
+ } else if (size > 0) {
+ ret = asprintf(&extra, "_%" PRIu64, count);
+ } else if (suffix) {
+ ret = asprintf(&extra, "%s", suffix);
+ }
+ if (ret < 0) {
+ PERROR("Allocating extra string to name");
+ goto error;
+ }
+
/*
* If we split the trace in multiple files, we have to add the count at the
* end of the tracefile name
*/
- if (size > 0) {
- ret = asprintf(&path_name_id, "%s_%" PRIu64, full_path, count);
+ if (extra) {
+ ret = asprintf(&path_name_suffix, "%s%s", full_path, extra);
if (ret < 0) {
- PERROR("Allocating path name ID");
- goto error;
+ PERROR("Allocating path name with extra string");
+ goto error_free_suffix;
}
- path = path_name_id;
+ path = path_name_suffix;
} else {
path = full_path;
}
ret = out_fd;
error_open:
- free(path_name_id);
+ free(path_name_suffix);
+error_free_suffix:
+ free(extra);
error:
return ret;
}
*/
LTTNG_HIDDEN
int utils_rotate_stream_file(char *path_name, char *file_name, uint64_t size,
- uint64_t count, int uid, int gid, int out_fd, uint64_t *new_count)
+ uint64_t count, int uid, int gid, int out_fd, uint64_t *new_count,
+ int *stream_fd)
{
int ret;
+ assert(new_count);
+ assert(stream_fd);
+
ret = close(out_fd);
if (ret < 0) {
PERROR("Closing tracefile");
(*new_count)++;
}
- return utils_create_stream_file(path_name, file_name, size, *new_count,
- uid, gid);
+ ret = utils_create_stream_file(path_name, file_name, size, *new_count,
+ uid, gid, 0);
+ if (ret < 0) {
+ goto error;
+ }
+ *stream_fd = ret;
+
+ /* Success. */
+ ret = 0;
+
error:
return ret;
}
*
* @param str The string to parse.
* @param size Pointer to a size_t that will be filled with the
- * resulting size.
+ * resulting size.
*
* @return 0 on success, -1 on failure.
*/
+LTTNG_HIDDEN
int utils_parse_size_suffix(char *str, uint64_t *size)
{
regex_t regex;
end:
return ret;
}
+
+/*
+ * fls: returns the position of the most significant bit.
+ * Returns 0 if no bit is set, else returns the position of the most
+ * significant bit (from 1 to 32 on 32-bit, from 1 to 64 on 64-bit).
+ */
+#if defined(__i386) || defined(__x86_64)
+static inline unsigned int fls_u32(uint32_t x)
+{
+ int r;
+
+ asm("bsrl %1,%0\n\t"
+ "jnz 1f\n\t"
+ "movl $-1,%0\n\t"
+ "1:\n\t"
+ : "=r" (r) : "rm" (x));
+ return r + 1;
+}
+#define HAS_FLS_U32
+#endif
+
+#ifndef HAS_FLS_U32
+static __attribute__((unused)) unsigned int fls_u32(uint32_t x)
+{
+ unsigned int r = 32;
+
+ if (!x) {
+ return 0;
+ }
+ if (!(x & 0xFFFF0000U)) {
+ x <<= 16;
+ r -= 16;
+ }
+ if (!(x & 0xFF000000U)) {
+ x <<= 8;
+ r -= 8;
+ }
+ if (!(x & 0xF0000000U)) {
+ x <<= 4;
+ r -= 4;
+ }
+ if (!(x & 0xC0000000U)) {
+ x <<= 2;
+ r -= 2;
+ }
+ if (!(x & 0x80000000U)) {
+ x <<= 1;
+ r -= 1;
+ }
+ return r;
+}
+#endif
+
+/*
+ * Return the minimum order for which x <= (1UL << order).
+ * Return -1 if x is 0.
+ */
+LTTNG_HIDDEN
+int utils_get_count_order_u32(uint32_t x)
+{
+ if (!x) {
+ return -1;
+ }
+
+ return fls_u32(x - 1);
+}
+
+/**
+ * Obtain the value of LTTNG_HOME environment variable, if exists.
+ * Otherwise returns the value of HOME.
+ */
+LTTNG_HIDDEN
+char *utils_get_home_dir(void)
+{
+ char *val = NULL;
+ val = getenv(DEFAULT_LTTNG_HOME_ENV_VAR);
+ if (val != NULL) {
+ return val;
+ }
+ return getenv(DEFAULT_LTTNG_FALLBACK_HOME_ENV_VAR);
+}
+
+/*
+ * With the given format, fill dst with the time of len maximum siz.
+ *
+ * Return amount of bytes set in the buffer or else 0 on error.
+ */
+LTTNG_HIDDEN
+size_t utils_get_current_time_str(const char *format, char *dst, size_t len)
+{
+ size_t ret;
+ time_t rawtime;
+ struct tm *timeinfo;
+
+ assert(format);
+ assert(dst);
+
+ /* Get date and time for session path */
+ time(&rawtime);
+ timeinfo = localtime(&rawtime);
+ ret = strftime(dst, len, format, timeinfo);
+ if (ret == 0) {
+ ERR("Unable to strftime with format %s at dst %p of len %lu", format,
+ dst, len);
+ }
+
+ return ret;
+}
+
+/*
+ * Return the group ID matching name, else 0 if it cannot be found.
+ */
+LTTNG_HIDDEN
+gid_t utils_get_group_id(const char *name)
+{
+ struct group *grp;
+
+ grp = getgrnam(name);
+ if (!grp) {
+ static volatile int warn_once;
+
+ if (!warn_once) {
+ WARN("No tracing group detected");
+ warn_once = 1;
+ }
+ return 0;
+ }
+ return grp->gr_gid;
+}
+
+/*
+ * Return a newly allocated option string. This string is to be used as the
+ * optstring argument of getopt_long(), see GETOPT(3). opt_count is the number
+ * of elements in the long_options array. Returns NULL if the string's
+ * allocation fails.
+ */
+LTTNG_HIDDEN
+char *utils_generate_optstring(const struct option *long_options,
+ size_t opt_count)
+{
+ int i;
+ size_t string_len = opt_count, str_pos = 0;
+ char *optstring;
+
+ /*
+ * Compute the necessary string length. One letter per option, two when an
+ * argument is necessary, and a trailing NULL.
+ */
+ for (i = 0; i < opt_count; i++) {
+ string_len += long_options[i].has_arg ? 1 : 0;
+ }
+
+ optstring = zmalloc(string_len);
+ if (!optstring) {
+ goto end;
+ }
+
+ for (i = 0; i < opt_count; i++) {
+ if (!long_options[i].name) {
+ /* Got to the trailing NULL element */
+ break;
+ }
+
+ optstring[str_pos++] = (char)long_options[i].val;
+ if (long_options[i].has_arg) {
+ optstring[str_pos++] = ':';
+ }
+ }
+
+end:
+ return optstring;
+}